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A093599 Composite numbers having an odd number of prime factors, all of which are distinct. 2
30, 42, 66, 70, 78, 102, 105, 110, 114, 130, 138, 154, 165, 170, 174, 182, 186, 190, 195, 222, 230, 231, 238, 246, 255, 258, 266, 273, 282, 285, 286, 290, 310, 318, 322, 345, 354, 357, 366, 370, 374, 385, 399, 402, 406, 410, 418, 426, 429, 430, 434, 435 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

First differs from A007304 at 2*3*5*7*11 = 2310, which is a(360) and thus beyond the tabulated range.

Subsequence of A030059. - Bill McEachen, Nov 06 2020

LINKS

Carl R. White, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Prime Sums

Wikipedia, Moebius function

MATHEMATICA

Select[Range[435], MoebiusMu[ # ] == -1 && Not[PrimeQ[ # ]] &] (* Alonso del Arte, Jan 24 2005 *)

PROG

(PARI) is(n)=my(f=factor(n)[, 2]); #f>2 && #f%2==1 && vecmax(f)==1 \\ Charles R Greathouse IV, Oct 19 2015

CROSSREFS

Cf. A007304, A030059.

Sequence in context: A238367 A225228 A336568 * A007304 A160350 A053858

Adjacent sequences:  A093596 A093597 A093598 * A093600 A093601 A093602

KEYWORD

nonn

AUTHOR

Eric W. Weisstein, Apr 03 2004

STATUS

approved

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Last modified April 20 06:59 EDT 2021. Contains 343125 sequences. (Running on oeis4.)